TY - JOUR
T1 - Reduction of oxidative stress by carvedilol
T2 - Role in maintenance of ischaemic myocardium viability
AU - Cargnoni, Anna
AU - Ceconi, Claudio
AU - Bernocchi, Palmira
AU - Boraso, Antonella
AU - Parrinello, Giovanni
AU - Curello, Salvatore
AU - Ferrari, Roberto
PY - 2000/8/18
Y1 - 2000/8/18
N2 - Objectives: To differentiate the impact of the β-blocking and the anti- oxidant activity of carvedilol in maintaining myocardium viability. Methods: Isolated rabbit hearts, subjected to aerobic perfusion, or low-flow ischaemia followed by reperfusion, were treated with two doses of carvedilol, one dose (2.0 μM) with marked negative inotropic effect due to β-blockage and the other (0.1 μM) with no β-blockage nor negative inotropism. Carvedilol was compared with two doses of propranolol, 1.0 - without - and 5.0 μM - with negative inotropic effect. Anti-oxidant activity was measured as the capacity to counteract the occurrence of oxidative stress and myocardium viability as recovery of left ventricular function on reperfusion, membrane damage and energetic status. Results: Carvedilol counteracted the ischemia and reperfusion induced oxidative stress: myocardial content of reduced glutathione, protein and non-protein sulfhydryl groups after ischaemia and particularly after reperfusion, was higher in hearts treated with carvedilol, while the myocardial content of oxidised glutathione was significantly reduced (0.30 ± 0.03 and 0.21 ± 0.02 vs. 0.39 ± 0.03 nmol/mg prot, both P <0.01, in 0.1 and 2.0 μM). At the same time, carvedilol improved myocardium viability independently from its β-blocking effect. On the contrary, propranolol maintained viability only at the higher dose, although to a lesser extent than carvedilol. This suggests that the effects of propranolol are dependent on energy saving due to negative inotropism. The extra- protection observed with carvedilol at both doses is likely due to its anti- oxidant effect. Conclusions: Our data show that the anti-oxidant activity of carvedilol is relevant for the maintenance of myocardium viability. (C) 2000 Elsevier Science B.V.
AB - Objectives: To differentiate the impact of the β-blocking and the anti- oxidant activity of carvedilol in maintaining myocardium viability. Methods: Isolated rabbit hearts, subjected to aerobic perfusion, or low-flow ischaemia followed by reperfusion, were treated with two doses of carvedilol, one dose (2.0 μM) with marked negative inotropic effect due to β-blockage and the other (0.1 μM) with no β-blockage nor negative inotropism. Carvedilol was compared with two doses of propranolol, 1.0 - without - and 5.0 μM - with negative inotropic effect. Anti-oxidant activity was measured as the capacity to counteract the occurrence of oxidative stress and myocardium viability as recovery of left ventricular function on reperfusion, membrane damage and energetic status. Results: Carvedilol counteracted the ischemia and reperfusion induced oxidative stress: myocardial content of reduced glutathione, protein and non-protein sulfhydryl groups after ischaemia and particularly after reperfusion, was higher in hearts treated with carvedilol, while the myocardial content of oxidised glutathione was significantly reduced (0.30 ± 0.03 and 0.21 ± 0.02 vs. 0.39 ± 0.03 nmol/mg prot, both P <0.01, in 0.1 and 2.0 μM). At the same time, carvedilol improved myocardium viability independently from its β-blocking effect. On the contrary, propranolol maintained viability only at the higher dose, although to a lesser extent than carvedilol. This suggests that the effects of propranolol are dependent on energy saving due to negative inotropism. The extra- protection observed with carvedilol at both doses is likely due to its anti- oxidant effect. Conclusions: Our data show that the anti-oxidant activity of carvedilol is relevant for the maintenance of myocardium viability. (C) 2000 Elsevier Science B.V.
KW - Adrenergic (ant)agonists
KW - Free radicals
KW - Ischemia
KW - Ventricular function
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U2 - 10.1016/S0008-6363(00)00082-1
DO - 10.1016/S0008-6363(00)00082-1
M3 - Article
C2 - 10963728
AN - SCOPUS:0034683047
VL - 47
SP - 556
EP - 566
JO - Cardiovascular Research
JF - Cardiovascular Research
SN - 0008-6363
IS - 3
ER -